PIKETON, Ohio — On a grassy compound in southern Ohio, Laura Tiu rounded up her recruits for boot camp.

The two dozen men and women standing before her on a recent Saturday fell quiet as she gave them marching orders: Stock the nearby ponds with perch and prawns.

The recruits are preparing not for a life in the Army but a life aquatic — as fish farmers.

Americans consumed 4.5 billion pounds of fish and shellfish in 2012, according to the National Oceanic and Atmospheric Administration.

That sizable appetite for seafood — along with a greater awareness of where our food originates — has translated into an increased interest in aquaculture, the fancy word for fish farming.

“Aquaculture is growing by leaps and bounds,” said Bob Calala, president of the Ohio Aquaculture Association, which has about 50 active members.

This year, the Ohio Department of Natural Resources has issued 235 aquaculture permits to fish farmers of all scales and sizes — up from 152 permits a decade earlier.

Years are often needed to learn to grow fish — to tackle the intricacies of aquaculture, from finding the best fit in fish breeds to navigating the channels of bureaucracy.

To help speed up the process, the Ohio Center for Aquaculture Research and Development at Ohio State University’s South Centers set up a yearlong boot camp to help newbie fish farmers enhance their aquaculture know-how.

“Aquaculture has a long learning curve,” said Tiu, who runs the aquaculture camp in Piketon. “It . . . (takes) about five years to get established in the industry, and what we’re trying to do is shorten those five years into one year.”

Aquaculture Boot Camp launched in 2013, offering free hands-on classes for about two dozen students selected to participate in the yearlong program, which includes homework in addition to monthly eight-hour courses.

The latest crop of 23 campers (ranging in age from 20-something to 60-something) meets one Saturday a month to learn the ABCs of aquaculture, from regulating water quality to stocking ponds.

The students spend some time in the classroom exploring the business side of aquaculture, but the rest of the day unfolds outside, near plots of corn and berries about 65 miles south of Columbus.

The June session started with a concept that seemed too simple to even merit a lesson: counting fish.

How hard can that be?

Very, it turns out, when you’re dealing with thousands of wiggly, squirmy fingerlings the size of pen caps.

But if you’re going to sell fish — whether for bait or food — you need to know how many you’re selling.

A couple of students grabbed nets, headed to circular tanks and stirred the water like witches and warlocks around a caldron.

The fish farmers in training scooped up some yellow perch and weighed them. Later, they counted some by hand, plunking the fish into buckets and clicking a counter as they released them into tanks.

“Two hundred and seventy-three,” said 34-year-old Zac Van Frank, who lives near Cincinnati. “That’s a lot of clicks.”

Although Van Frank and the rest of the students worked with yellow perch and prawns last month, he and some of his classmates have been drawn to tilapia on their farms.

Tilapia — an increasingly popular warm-water fish known for its not-so-fishy flavor — might not readily come to mind when thinking of a relatively cold state such as Ohio, but it has been proving popular with aquaculture novices here.

Rodriguez, along with about half of the 20 students who graduated with him, is putting his fish-farming knowledge to use, if on a tiny scale.

In January, Rodriguez and his wife, Marta Morales, got rid of the couches in their Powell living room to make space for fish tanks.

Now, tilapia swim a few feet away from their dining-room table.

Hundreds of baby fish also claimed space in the garage, and some of them might soon inhabit the couple’s hot tub when they outgrow their current tanks.

Rodriguez recently sold a few dozen baby fish to an aquaculture supplier, and he hopes to sell or give away more in the future. For now, though, he is focused mainly on practicing the skills he learned at the boot camp.

“Theory is one thing,” he said, “but practice is another.”

It doesn’t hurt when such practice is free.

Thanks to a $550,000 federal grant, Rodriguez and the rest of the 2013 boot-camp students — as well as the 2014 class members — didn’t pay for the courses.

The 2015 students will probably have to shell out cash for the program because the federal funding covered just two years of camp.

Organizers are still trying to determine the fee for 2015, but they hope to continue the program.

“The boot camp really has given me a . . . wider base and a broader perspective of the aquaculture industry,” said Bell, who with his wife raises thousands of tilapia in indoor tanks on their farm near Frazeysburg.

“It’s priceless.”

Bell, 50, sells live tilapia to people in the community and to haulers who take the fish to markets in Chicago, New York and Toronto.

He and his wife also secured a federal grant to help them with the fish farming, and Bell quit his job as a facilities manager in February 2013 to pursue aquaculture full time.

Many of his classmates, however, are just testing the aquaculture waters.

Lori Klintworth, for example, doesn’t have any fish yet, but the 54-year-old is interested in raising catfish and growing lettuce and other plants in water in the northeastern Ohio village of Apple Creek, where she lives.

“There’s so much unhealthiness in our food, with pesticides and herbicides,” she said. “We wanted to know where our food was coming from and what’s in it.”